Fast real-time polymerase chain reaction for quantitative detection of Lactobacillus delbrueckii bacteriophages in milk.
One of the main microbiological problems of the dairy industry is the susceptibility of starter bacteria to virus infections. Lactobacillus delbrueckii, a component of thermophilic starter cultures used in the manufacture of several fermented dairy products, including yogurt, is also sensitive to bacteriophage attacks. To avoid the problems associated with these viruses, quick and sensitive detection methods are necessary. In the present study, a fast real-time quantitative polymerase chain reaction assay for the direct detection and quantification of L. delbrueckii phages in milk was developed. A set of primers and a TaqMan MGB probe was designed, based on the lysin gene sequence of different L. delbrueckii phages. The results show the proposed method to be a rapid (total processing time 30 min), specific and highly sensitive technique for detecting L. delbrueckii phages in milk.
Martín
Maria Cruz
MC
Instituto de Productos Lácteos de Asturias (CSIC), Apdo. de Correos 85, 33300 Villaviciosa, Asturias, Spain.
del Rio
Beatriz
B
Martínez
Noelia
N
Magadán
Alfonso H
AH
Alvarez
Miguel A
MA
D000818:Animals; D001435:Bacteriophages / Q000302:isolation & purification*; D002417:Cattle; D003257:Consumer Product Safety; D005285:Fermentation; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D048668:Lactobacillus delbrueckii / Q000821:virology*; D008892:Milk / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity